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Influence of Superior Attachment of the Uncinate 10.5005/jp-journals-10013-1257Process on the Presence of Agger Nasi Original article

Influence of Superior Attachment of the Uncinate Process on the Presence of Agger Nasi 1Rahul Shivaraj, 2Cimona Dsouza, 3George Pinto

ABSTRACT surgery is still considered difficult with increased risk Objective: The superior attachment of the uncinate process and high chances of failure rate. The endonasal approach and the agger nasi cell are important landmarks in to frontal sinus and frontal recess for frontal sinusitis surgery and are in close relation with each other. The aim of is challenging and the most difficult part. A thorough this study is to investigate the relationship between the two. knowledge about the regional anatomy is required due Study design: A retrospective radiological study. to the compact nature of this region, high anatomic Materials and methods: A total of 50 patients with features variability of surrounding structures, and close relation of chronic sinusitis were evaluated radiographically, i.e., by with the vital organs like and anterior base.1 computed tomography. Hundred sides, i.e., 50 scans, were The position of the superior attachment of the uncinate evaluated for superior attachment of the uncinate process process and the extensive pneumatization of the and the presence of agger nasi. Chi-square test was used as a statistical tool for eliciting the relationship between the two. surrounding ethmoid air cells including the agger nasi may all limit the shape and width of frontal recess and Results: The agger nasi cell was found in 68 (68%) of 100 2 sides. The prevalence of agger nasi cell according to the lead to frontal sinus disease. Wormald proposed that superior attachment of uncinate process types was 64.1% pneumatization of the agger nasi cell affects the superior for lamina papyracea, 79.41% for skull base, and 53.84% for attachment of the uncinate process. In our study, our aim middle turbinate. The presence of agger nasi cell according was to determine a statistical relationship between the to the superior attachment types of uncinate process was not statistically significant (χ2 = 3.5925, p = 0.16592). agger nasi and the superior attachment of the uncinate process. Conclusion: The agger nasi cell was found in 68 sides (68%), and there was no statistical significance between the superior attachment of the uncinate process and the presence of agger MATERIALS AND METHODS nasi cell. Patients between 20 and 80 years with chronic sinusitis Keywords: Agger nasi, Frontal sinus, Superior attachment of were evaluated radiologically using coronal computed the uncinate process. tomography (CT) or . A retrospective How to cite this article: Shivaraj R, Dsouza C, Pinto G. descriptive radiological study was carried out between Influence of Superior Attachment of the Uncinate Process on September 2012 and September 2014. Patients with the Presence of Agger Nasi. Clin Rhinol An Int J 2016;9(1):21-23. a history of facial trauma, surgery, and tumors were Source of support: Nil excluded. Fifty consecutive coronal CT scans, i.e., 100 Conflict of interest: None sides, were evaluated for the superior attachment of uncinate process and the presence of agger nasi. INTRODUCTION RESULTS Since the discourses of Messerklinger and Wigand in the In our study of 50 cases (100 sides), the superior attach- late 1970s, sinus surgery has undergone a tremendous ment of the uncinate process to lamina papyracea was expansion with advanced imaging and increased found in 53 sides, to skull base in 34 sides, and to middle understanding of anatomy and pathophysiology of turbinate in 13 sides (Figs 1 to 3). Agger nasi was present chronic sinusitis. With all this, endoscopic frontal sinus in 68 sides out of 100; 33 were bilateral and 2 were unilateral (Fig. 4). A total of 34 agger nasi were found 1,2Postgraduate Student, 3Professor and Head in association with the superior attachment of the unci- 1-3Department of ENT, Father Muller Medical College nate process to lamina papyracea, 27 with attachment to Mangaluru, Karnataka, India skull base, and 7 with attachment to middle turbinate. Corresponding Author: Rahul Shivaraj, Postgraduate The prevalence of agger nasi according to the superior Student, Department of ENT, Father Muller Medical College attachment of the uncinate process was 64.1% to lamina Mangaluru, Karnataka, India, Phone: +918867734257, e-mail: papyracea, 79.41% to skull base, and 53.84% to middle [email protected] turbinate (Table 1). Statistically, a chi-square value of Clinical Rhinology: An International Journal, January-April 2016;9(1):21-23 21 Rahul Shivaraj et al

Fig. 1: Bilateral superior attachment of uncinate process to lamina Fig. 2: Superior attachment of uncinate process to skull base papyracea. Solid black arrow on right side; transparent black (white arrows) arrow on left side

Fig. 3: Superior attachment of uncinate process to middle Fig. 4: Agger nasi cell on left side (black arrow) turbinate (white arrows)

Table 1: Frequency distribution of agger nasi cell according to widens superiorly into the frontal sinus and inferiorly the superior attachment of uncinate process into the frontal recess. Although frontal ostium is the Number (%) Number (%) of narrowest part, it is rarely a direct source of frontal sinus UP superior attachment of sides agger nasi cell outflow tract obstruction. The inferior third part of the Lamina papyracea 53 (53) 34 (64.1) Skull base 34 (34) 27 (79.41) frontal sinus pathway formed by the frontal recess is the Middle turbinate 13 (13) 7 (53.84) anatomical location responsible for most cases of frontal sinusitis. The frontal recess is a narrow inverted funnel- shaped cleft within the anterior ethmoid complex that 3.5925, with p-value of 0.16592, was obtained, thereby widens in the posterior and inferior direction.2-4 indicating that the relationship between the superior The superior attachment of the uncinate process attachment of the uncinate process and agger nasi is not was first referred by Stammberger et al5 in 1991, and statistically significant. described three possible extensions, i.e., to the lamina papyracea, skull base, and middle turbinate (Figs 1 to 3). DISCUSSION Recently, a more detailed classification was given by Frontal sinus drains into the via frontal Landsberg and Friedman6 classifying the variation of ostium. The frontal ostium region on the sagittal section superior attachment into six types. In our study, we is an hour-glass-shaped structure with the narrowest considered Stammberger and Hawke’s classification part located at the frontal ostium. The frontal ostium for the superior attachment of the uncinate process. 22 AIJCR

Influence of Superior Attachment of the Uncinate Process on the Presence of Agger Nasi

The superior attachment of the uncinate process is an CONCLUSION important anatomical structure for the frontal recess Superior attachment of the uncinate process to lamina region. Landsberg and Friedman6 defined two types of papyracea was the most common. Agger nasi was frontal sinus outflow tracts depending on the superior found to be present in 79.41% cases of uncinate process attachment of the uncinate process.7 When the uncinate attachment to skull base, a rate that varies from that process inserts into the lamina papyracea, the ethmoidal noted in the literature. However, we found no statistically infundibulum is closed superiorly to form a blind pouch significant relation between the superior attachment of called recessus terminalis.8 In this case, the frontal recess the uncinate process and agger nasi. Further studies directly communicates with the middle meatus or the are needed to investigate the relationship between the suprabullar recess9 and this communication was only degree of pneumatization of agger nasi and the superior 1%;10 thus, practically it opens into the middle meatus in attachment of the uncinate process, and their influence the case of recessus terminalis. Here it is limited laterally in causing frontal sinusitis. by the uncinate process and medially by the lateral side of the middle turbinate, or the junction of the middle REFERENCES turbinate and the cribriform plate. The frontal recess drains via the ethmoidal infundibulum into the middle 1. Jacobs JB. 100 years of frontal sinus surgery. Laryngoscope 1997 Nov;107(11 Pt 2):1-36. meatus when the uncinate process is attached medially 2. Wormald PJ. The agger nasi cell: the key to understanding 6 to the skull base of the middle turbinate. These findings the anatomy of the frontal recess. 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In this study also, population. Rhinology 2010 Jun;48(2):239-244. 13. Ercan I, Cakir BO, Sayin I, Başak M, Turgut S. Relationship no significant relationship was found. Similarly, in our between the superior attachment type of uncinate process study of 100 sides, we found no significant statistical and presence of agger nasi cell: a computer-assisted anatomic relationship between the two structures. study. Otolaryngol Head Neck Surg 2006 Jun;134(6):1010-1014.

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